Paolo broke my heart. We parted at midday, on a bleak New York City sidewalk. Tall, dark and irresistibly handsome, Paolo never looked back. But this was no ordinary breakup.

I am still married to my husband of more than 20 years, and far from a threat, Paolo had been embraced as a companion for us both. Instead, this five-year-old black Labrador Retriever became a vehicle of guilt and anguish as well as a source of grinding tension between two deeply committed dog people. Our hearts were full of hope and happiness when we welcomed Paolo into our lives. Our souls were wracked with sorrow and shame when we gave him up.

It would be tempting to say that Paolo was not a homewrecker. But in truth, he managed to wreck just about anything with which he came in contact. Paolo ate pillows, photo albums, tax records. He killed several Kong toys and, on his second day in our house, took a hunk out of my husband’s hand while playing tug-of-war. We soon realized that what we had adopted was not a dog, but an 85-pound weapon of mass destruction.

Still, we were both hopelessly besotted, and determined to save Paolo’s canine soul. As with any off-kilter relationship, we believed we could fix it. Love would conquer all, right? Wrong. Sometimes the hardest lesson of all is learning that some damage needs real experts to repair it.

After the death of our elderly black Lab, about three months passed before I began trolling for another dog. On the Internet, Paolo looked perfect. He was a big, sturdy adult with a strong, square head and a glossy coat. But it was not so much his looks as his narrative that intrigued me. The rescue agency explained that five-year-old Paolo was a Bernie Madoff victim. His previous owners had lost all their assets when Madoff ’s fraudulent financial empire fell to ruins. Forced from their Park Avenue digs, they could no longer keep Paolo. Dog people tend to see the world — and financial scandal — in peculiar terms. All I could think was: bad enough that so many people had their lives upended by Bernie Madoff’s avarice, but a dog?

The rescue agency welcomed our application to relocate Paolo from Manhattan to a leafy hamlet near Boston. We were experienced Lab owners who promised long daily walks in a forest and summers in a seaside cottage. Our two previous rescue dogs had lived long, full lives. When we were invited to Manhattan for an interview and a chance to meet Paolo, the occasion was fraught with such expectation that my husband wondered if he should wear a suit.

A week later, I was back in New York City, this time with my car. It took two burly handlers and a mountain of treats to lure Paolo into the crate that occupied the entire back seat. Still, the canine behavioral psychologist — an occupation I had never heard of until then — assured us that Paolo would relax comfortably in a secure new environment.

In the weeks to come, I would remember the midwestern mother who shipped her adopted son back to Russia. When I read that story, I wanted to throttle the woman for heartlessly disrupting a child’s life. Now I reconsidered. Beyond his insatiable appetite for any object he could wrap his jaws around, Paolo also confused our rugs with outdoor surfaces. In what quickly became a pattern of daily phone calls and emails, the canine behavioral psychologist sounded indignant when I questioned whether this middle-aged dog was, in fact, housebroken. Then he admitted that the previous owners had Astroturfed their front hall to avoid taking Paolo outside.

Indeed, Paolo hated anything resembling nature. He ignored shrubs and trees and refused to walk on anything but asphalt. Squirrels bored him, and he disdained other dogs. His behavior was so troubling that I enlisted the help of a legendary, no-nonsense dog trainer. She quickly concluded our entire family would need daily sessions with Paolo. I wondered exactly how I was supposed to fit my job into that equation.

One immediate issue was what the trainer and the dog shrink agreed was Paolo’s attachment disorder. Briefly, this meant he would not let me out of his sight, challenging even my husband for my full attention. Imagine the surprise of my university colleagues when I showed up at faculty meetings with an 85-pound lap dog — who, as it happened, snored loudly. In a stroke of genius mixed with desperation, I engaged a professional dog-walking service to come to my office and take Paolo for regular strolls. Both the trainer and the doggie shrink agreed that this would help to both socialize Paolo and reduce his separation anxiety.

The same affable young male dog walker came twice a day — until day three, when he knocked on my office door and Paolo attacked him. This sturdy, six-foot-tall person was pinned against the wall, eyeball to eyeball with a snarling, lunging animal. Eventually, distracted by a leftover breakfast bagel, Paolo released his terrified prey. At that moment, I realized I could not trust this dog. What if he had turned on a child or an old person? Already, Paolo was more of a project than a pet. Now he had become a liability.

The trainer and canine behavioral psychologist concurred that Paolo should be reclassified as a special-needs dog. The shrink said Paolo had probably been in shelter shock at the rescue agency: that is to say, falsely subdued. He said owners often misrepresented the animals they brought in for adoption. And he thanked me profusely for the long memo I prepared describing Paolo’s behavior outside the shelter.

None of which made the decision to take him back any easier. On the four-hour drive back to Manhattan, Paolo slept peacefully until we edged into the city. Suddenly he shot up and shoved his snout through the small opening in the window, deliriously inhaling his beloved urban smells. I was weeping when the behavioral psychologist met us on the sidewalk, and I cried most of the way home. Paolo, the dog shrink promised in an email the next day, was doing just fine.

Postscript
For months I dreamed about Paolo. I fretted endlessly, but resisted the urge to contact the rescue agency because I knew separation was best for both of us. When, finally, I broke down and called, the news was good. At least one placement subsequent to ours had not worked out, but now Paolo was headed to a tryout in what everyone hoped would be a forever home with a family experienced in caring for troubled animals. “Fingers crossed,” said the agency official who had worked with us many months before.

This story has a further happy ending. After taking Paolo back to New York, I felt like a heel, unworthy of dog ownership. Then one day I found myself poring over Labrador rescue sites. This time we moved cautiously, sending a cool-headed friend to check out a promising candidate we identified in another state. Jackson, a 5-year-old black Lab, is asleep beside me as I write. He is the love of our lives.